Holly Kollenborn says it started more than a year ago with threatening notes posted on her back gate. "The first note said, 'Your dog was barking. If you don't do something about it, I will,'" she said. "The second note said, 'Your dog was barking. If it happens again, I'll kill your dog.'"

Then two weeks ago, Kollenborn found herself rushing Jackson -- her four-year-old purebred Cavalier Spaniel -- to the pet hospital. He had eaten canned dog food a stranger left for him in a zip-lock baggy in his backyard.

"They discovered he was poisoned with antifreeze," said Kollenborn. "There was antifreeze mixed in with the canned dog food."
For Jackson, it was a slow, agonizing death.

"He was having liver and kidney problems, so I had to put him down," Kollenborn said.

Police started investigating and found something of a pattern: other neighbor's pets have been threatened and/or poisoned off and on over the past seven years on Iris Court. One woman's retriever got a threatening note. A cat was another recent victim.

"She had some type of chemical in her system similar to rat poison," the cat owner said. "We caught it early so she didn't die. She had a few blood transfusions."